Fourier-transformed infrared (FTIR) spectroscopy for detecting milk powder addition in Cyprus goat milk: a preliminary study for future adulteration detection in halloumi cheese

This study was about the adulteration of milk with milk powder and serves as a precursor for future studies on halloumi cheese adulteration with milk powder. Three different commercial milk powders of different geographic origins were tested to check the impact of milk powder origin versus the amount of milk powder added in milk as an adulterant. Three different concentrations of skim milk powder (SMP) were added (0.5%, 1%, and 3%) to Cyprus goat milk, and the mixtures were then heated to 90°C (a crucial step in halloumi cheese preparation). Fourier-transformed infrared (FTIR) spectra were collected after freeze-drying, and Partial Least Squares Discriminant Analysis, a supervised classification method, was applied in terms of chemometrics to test the classification of samples. The adulterated milk samples of this study are used in halloumi cheese making to check after cooking the discrimination of adulterated halloumi cheese at low percentage of adulteration with SMP by applying FTIR and chemometrics in future. Based on the present study, the origin of milk powder is not significant, and it is assumed that generally, for future studies the origin of milk powder will not affect sample classification.